Heat engines using air, steam, mixtures of air and steam, and other working media have been suggested, and most of these use a single gaseous fluid as a working medium. The steam engine, and especially the steam turbine, has been the most popular and successful heat engine, and present commercial steam engines have maximum efficiencies of less than 40% in converting the energy available from fuel into shaftwork. Steam engines and other workable heat engines have used a heat sink, usually in the form of a condenser, where unavailable heat of condensation is discarded, and vapor cycles such as the Rankine cycle and thermodynamic cycles for other heat engines as explained in many texts all require a heat sink where energy is unavoidably discarded.
The invention arose from thermodynamic comparisons between heat engines and weather phenomena, which produce enormous energy exchanges involving the latent heat of condensation and fusion, and the invention recognizes ways that similar energy transfers involving the latent heat of condensation or fusion can be put to practical use in heat engines and other thermodynamic processes under human control to eliminate the need to discard energy to a heat sink and to greatly increase efficiencies. Natural weather phenomena occur from a mixture of air and water vapor at relatively low temperatures and pressures compared to steam engines, and the invention involves recognition of ways that similar mixtures of air or other gaseous fluids with water vapor or other vapors can produce energy transfers that can be put to practical and efficient uses in heat engines and other devices involving thermodynamic processes. The substantial increase in efficiency and the lower operating temperatures and pressures used in practicing the invention also lead to use of many different heat sources than are presently practical for steam engines, use of liquid energy storage systems, use of heat wasted from other processes, and enormous reductions in the heat energy required for producing shaftwork, electricity, and multitudes of by-products.